About Territory Alignments: Major, Intermediate, and Minor
There are three types of territory alignment:
Major. Typically, you run major alignments when you run an alignment for a sales force for the first time and when you make significant changes to an alignment. Major alignments provide a full refresh of the alignment. To a first approximation, the major alignment drops all existing rules from the territories and adds the new rules from the major alignment.
Minor. Typically, you run minor alignments when you are making smaller changes to a sales force that has already been aligned. To improve performance, the minor alignment processes only the minimum number of objects needed to change the current alignment, maintaining the alignment by both adding and dropping rules. You cannot change position rules in minor alignments.
Intermediate. Intermediate alignments take the current alignment into account, and they process all objects based on all active rules, including Active Territory Rule (without Effective End Date or Effective End Date greater than Today) and Add and Drop Rules for Alignment, so their performance is not as fast as minor alignments. You can run intermediate alignments if you want to change position rules but do not want to run a full alignment.
You can activate minor and intermediate alignments only after at least one major alignment has been activated. You can activate alignments only for primary hierarchies.